Optical tomography is an imaging technique of objects and their internal structure that is based on analysis of a signal created from a light reference beam and a light object beam, which is back-scattered by object internal structures and interferences with the light reference beam and forms a resultant light beam. The resultant light beam is directed onto a dispersion device, for example a diffraction grating, and then is registered by a detection device or a spectrum recorder, for example, a matrix of photosensitive elements used in a linear CCD camera. The electrical signal in a form of a digital signal generated by the matrix is transmitted to a calculation unit and information about the axial structure of the object being examined is received by means of numerical calculation in the calculation unit, for instance by means of a PC.
Apparatuses to produce imaging of objects by means of optical tomography are known in numerous variants. For example, a method for fast object imaging using spectral optical tomography in which, to increase the speed of object imaging, a matrix of sensitive elements with a memory to store information about scanned fragments of the object is described in the publication of international application No. WO 2004/043245 A1.
From the paper entitled “Full range complex spectral optical coherence tomography,” M. Wojtkowski, A. Kowalczyk, R. Leitgeb, and A. F. Fercher, Opt. Lett. 27, 1415-1418 (2002) is known a method for imaging the interior structure of objects, in which two or more spectrum measurements at each position of the object light beam may be performed.
In turn, the publication of international patent application No. WO 2006/017837 A2 describes a process, system and software arrangement to determine at least one position of one portion of sample using an optical coherence tomography.
Additionally, from the publication of international patent application No. WO 2006/036717 A2 is known an optical feedback between two interferometers for taking desired measurements of length differences of optical paths of two light beams.
Furthermore, the publication of US patent application No. US 2005/0036150 A1 describes a method for imaging of concentration and displacement of a specific agent in an examined object using an optical coherence tomography.
In addition, form the publication of UK patent application No. GB 2416451 A is known a method of detecting images of objects using a laser-scanning microscope with linear scanning.
From the publication No. WO2007003288 of the international application entitled “Fourier domain optical coherence tomography employing a swept multi-wavelength laser and a multi-channel receiver” is known a system, which comprises a swept multi-wave length laser, an optical interferometer and a multi-channel receiver. By employing a multi-wavelength laser, the sweeping range for each lasing wavelength is substantially reduced as compared to a pure swept single wavelength laser that needs to cover the same overall spectral range.
From the publication No. WO2007016296 of the international application entitled “Optical coherence imaging systems having a reduced effective linewidth and methods of using the same” are known frequency domain optical coherence imaging systems, which have an optical source, an optical detector and an optical transmission path between the optical source and the optical detector. The optical transmission path between the optical source and the optical detector reduces an effective linewidth of the imaging system. The optical source may be a broadband source and the optical transmission path may include a periodic optical filter.
Among the above-described, known imaging techniques, based on the optical tomography method, the best results for eye imaging are achieved by SOCT, characterised by high longitudinal resolution, fast measurement speed and high sensitivity. However, the tomography equipment created to date, based on this method, also has the limitations, for instance, the accuracy of imaging of objects depends on adjusting the apparatus to work conditions and regulation that should be carried out after out of tuning of the apparatus due to vibration during transport, change of temperature and new work condition of the apparatus. Nowadays used regulation systems are hand maintained, not precise, time consuming and need to be maintained by users that have been trained in the field of the imaging of objects by means of optical tomography.